1. Field of the Invention
The present invention relates to a controlling technology of a computer peripheral component, more particularly to a keyboard/mouse switching controller and control method thereof. The present invention is applied to a computer system where a keyboard and a mouse have the same connectors. The present invention switches the keyboard signal and the mouse signal selectively, thereby transmitting the keyboard signal and the mouse signal to the computer system correctly.
2. Description of the Related Art
In the present day, mice and keyboards are basic input device of the computer systems. As to the ATX main board standards proposed by Intel, mice and keyboards have the same interface called the PS/2 interface. The PS/2 interface is a standard proposed by IBM in 1987. The PS/2 interface comprises a data pin (pin-1), a clock pin (pin-5), a ground pin (pin-3) and a power pin (pin-4). Pin-2 and pin-6 are not used. FIG. 1 is a schematic diagram illustrating the conventional mouse/keyboard interface structure in computer systems. In FIG. 1, a keyboard connector 10 is coupled to a keyboard/mouse controller 14 by a keyboard data signal line KDAT and a keyboard clock signal line KCLK. A mouse connector 12 is coupled to the keyboard/mouse controller 14 by a mouse data signal line MDAT and a mouse clock signal line MCLK. The keyboard/mouse controller has a basic input/output system (hereinafter referred to as a controller BIOS), thereby transmitting data to a host interface. For example, the keyboard/mouse controller is a 8042 microcontroller. However, a user assembling a computer may be confused when installing the mouse and the keyboard because both the keyboard connector and the mouse connector are PS/2. If the user mistakenly connects the mouse to the keyboard connector and/or the keyboard to the mouse connector, the computer system is interrupted and doesn't work normally.